IRIS Community Response to the Great Chile Earthquake of 2010
Abstract
The Mw=8.8 Maule earthquake off the coast of Chile on February 27, 2010 is the 5th largest megathrust earthquake ever to be recorded and the 2nd largest to be recorded by modern digital seismic networks. Immediately following the Maule earthquake, teams of seismologists from Germany, France, the UK, and the US, working with seismologists in Chile, coordinated resources to deploy both broadband and short period seismometers and accelerometers above the rupture zone to capture aftershocks associated with this significant earthquake. The U.S. IRIS Community response involved deployment of 59 broadband and 4 combined broadband and accelerometer stations spanning the rupture region of the main shock from 33-38.5°S and from the coast to the Andean range front. Four of these stations were subsequently upgraded for real-time telemetry, and these data have been freely available from the IRIS DMC since shortly after they came online. Data recorded at these stations will be combined to produce an open international community data volume providing an unprecedented opportunity to investigate processes associated with great earthquakes and to image the anatomy of a subduction zone. Scientific objectives potentially attainable using this unique data set fall into two general categories: (1) rupture processes of megathrusts, and (2) active tectonics and dynamics of an oceanic-continental (Andean) margin. For example, the relatively dense station spacing - 30 km - of the IRIS CHAMP (Chile RAMP) broadband seismic network will facilitate investigation into the character of the aftershock zone in the low-slip regions of the main shock to determine if these regions are locked or creeping, and whether these states are governed by variations in temperature or fluid content. The dataset also offers opportunities to generate higher resolution images of the seismogenic zone, forearc wedge, and subducting slab, that can reveal the role that spatial changes in material properties play in seismogenesis and slab dynamics. We can take advantage of data collected before the event at collocated stations to investigate secular changes in the properties of the medium in the rupture zone or upper plate, which can further elucidate the role of fluids in the seismogenic zone.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFM.G33A0811M
- Keywords:
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- 7209 SEISMOLOGY / Earthquake dynamics;
- 7240 SEISMOLOGY / Subduction zones